摘要
对于TFD和TMVD混合集约束的时态模式来说,由于多时间粒度的使用使成员籍问题的解决变得更加复杂.由于成员籍问题的解决对设计有效的模式分解算法必不可少,由此定义了时态类型集的强封闭集、属性集的有限闭包、属性集在给定时态类型上的有限依赖基、属性集的有限依赖基及特殊有限依赖基等概念,给出了求属性集的有限闭包、有限依赖基和特殊有限依赖基、时态混合集成员籍问题的算法,并对算法的可终止性、正确性进行了证明,对时间复杂性进行了分析.
For temporal scheme with temporal functional dependencies and temporal multivalued dependencies constraints, the usages of multiple time granularities make it more difficult to solve the membership problem. However, the solution of the membership problem is essential to design an available algorithm of scheme decomposition. Thus, in this paper, strong close set of set of temporal types, finite closure of attribution sets, finite dependency base of attribution sets based on a certain temporal type, finite dependency base of attribution sets and special finite dependency base of attribution sets are introduced; the algorithm of finite closure, finite dependency base of attribution sets and special finite dependency base of attribution sets, and the membership problem is given; and the algorithm＇s termination and correction are proved.
出处
《计算机研究与发展》
EI
CSCD
北大核心
2006年第7期1267-1272,共6页
Journal of Computer Research and Development
基金
黑龙江省自然科学基金项目(F0006)
关键词
时态数据库
有限闭包
有限依赖基
特殊有限依赖基
成员籍
temporal database
finite closure
finite dependency base
special finite dependency base
membership
